The golden ticket winners took to social media to pay tribute to the late Wilder.
Julie Dawn Cole, who played the bratty Veruca Salt, and Denise Nickerson, who played the gum-chomping Violet Beauregarde, expressed their condolences via Twitter.
"Such very sad news. Words not enough. Treasured memories," Cole wrote.
"RIP Gene. You were so talented and kindhearted. You will be sorely missed by so many. All of us have lost OUR Willy Wonka. Love, Violet" Nickerson tweeted.
Meanwhile, actor Paris Themmen, who played Mike Teevee, changed his cover photo to honor Wilder's life.